Arbitrum activated its ArbOS 61 “Elara” upgrade on August 20, introducing new developer tooling and optional compliance features for enterprise deployments. Following the activation, node operators are required to update to Nitro v3.11.3.
The upgrade's most notable addition is an optional, protocol-level compliance filtering feature designed specifically for private or enterprise Orbit chain operators. The feature allows operators to meet regulatory and legal obligations for use cases involving institutions and tokenized assets. The developer documentation emphasizes that the filtering is optional and configuration-dependent, rather than a blanket change applied to public Arbitrum One or Nova networks.
Stylus Contract Expansion
In addition to enterprise tooling, Elara expands the Stylus contract size limit from 24 KB to 96 KB. This increase aims to provide developers with greater flexibility for building larger or more complex smart contracts, potentially easing code migration for teams utilizing languages such as Rust, C, and C++.
Broader Ecosystem Impact
The Elara upgrade reflects Arbitrum's continued expansion beyond public rollups into custom, Ethereum-aligned networks via the Orbit chain framework. By offering customizable infrastructure—including permissioning, compliance tools, and expanded contract sizes—Arbitrum aims to better serve enterprise-focused deployments while maintaining network distinctions between public and private environments.
